Page 4. Distinctive qualities

Primitive survivors

Most New Zealand species are not very different from their
close relatives in other countries. But some are primitive
animals that have died out or are restricted elsewhere. Some
have been in New Zealand for at least 85 million years.
Others arrived after New Zealand split from Gondwana.

The speed with which introduced rats, mice, stoats and
other mammalian predators have recently wiped out many native
species gives a clue as to why primitive species endured for
millions of years. On other land masses, more sophisticated
competitors and predators evolved – primitive species became
extinct as a result. These competitors and predators were
absent in New Zealand, so primitive life flourished.

There are a number of primitive animals in New
Zealand:

The tuatara (Sphenodon) is the only surviving
member of a reptile group that existed before the dinosaurs
and was once common everywhere.

New Zealand wrens (Acanthisitta) are the
earliest passerine (perching) birds.

Ancient frogs (Leiopelmids) and insect-like creatures,
such as the Heterojapyx species, are nearly
unchanged since the Jurassic period (200–145 million years
ago).

The short-tailed bat (Mystacina) belongs in a
group by itself, and was unknown elsewhere until discovered
as a fossil in Australia.

Few plants can be categorised as primitive survivors,
although many are from old groups. Some of New Zealand’s
primitive plants, such as the flowering plant hutu
(Ascarina lucida), arrived recently (in the last 10
million years). Hutu is endemic – only found in New Zealand.
Other primitive groups, such as podocarps, are widely
distributed elsewhere.

Unusual features

Some features are shared by many New Zealand species,
making the group distinctive. Examples are flightlessness in
birds, gigantism in some animal groups, and white-flowered
plants.

New Zealand, in common with other isolated archipelagos
such as Hawaii, has a large number of radiations. This is
when one species rapidly evolves into many species. These may
be adapted to various environments, or have highly
distinctive forms, behaviours or habitats.